In the technical sector of the bottling of drinks, the use of mechanical clamping caps, typically of the screw or crown type and generally made of plastics material or metal, is known for the substantially hermetic sealing of bottles containing a variety of liquids. The hermetic seal is ensured by a seal, made for example of a plastics material, which is usually fixed to the surface of the cap that is facing the interior of the bottle.
These caps are particularly advantageous due to their relatively low cost and because they ensure a substantial seal.
In the specific sector of bottles of wine, the use of these caps substantially reduces the problem of the transfer of undesirable substances by common corks. In fact, the latter can damage a high percentage of bottles due to the release of trichloroanisole contained in the cork which causes the particular and undesirable taste and smell known by the term “corked”. Moreover, as cork is a natural material that has very variable weight and density, and consequently sealing and permeability, characteristics, its properties are “non-standard” and, in the case for example of bottles of wine, it may occur that, due to a poor hermetic seal of the corks, the content oxidises prematurely thus spoiling the taste.
Crown or screw caps, however, precisely because of their hermetic seal, are not usually recommended for the bottling of certain wines which, in order to age from an organoleptic point of view, require an exchange of air between the interior of the bottle and the exterior. They are used rather for bottling wines intended for more immediate consumption, in which this ageing period is not required. The use of hermetic caps for wines intended for long periods of ageing in the bottle would give rise to reduction processes which would compromise the organoleptic characteristics of the wine.